Video: Yellowfin Tuna Can’t Stop Shaking

Pound for pound, many anglers agree that yellowfin tuna are probably the best fighters of all big game tunas. Even out of the water, these fish can put up a formidable fight—especially when you’re least expecting it. This angler was holding up his most recent catch for a photo when the fish decided it was the perfect opportunity to make its escape. It also has a secret weapon.

Despite how it looks, the shaking is natural. Tuna have interlocking vertebrae which allows them stiffen their spines and vibrate intensely. In the water, this allows them to swim at super-high speeds, but it also serves a backup function of escaping from unwary anglers. Countless fish have escaped back to safe waters this way, but this fisherman decided to hold on for dear life. In return, he gets to keep his tuna—but probably got a nasty bruise on his bum.

It is not known if the fish was released, or where the video was filmed.